Celebrations broke out at BJP offices in Assam as election results began to be flashed on TV and confirmed the party was forming its second government in the Northeast.

The party first tasted power in the region in 2003, when Gegong Apang, the long-serving former Congress chief minister, took his supporters to the BJP and formed the government in Arunachal Pradesh.

The capture of power in Assam was less dramatic, though. The BJP was expected to prevail easily, although few had foreseen such an impressive scale of victory. Indeed, even Himanta Biswa Sarma had predicted, in an interview three days ago, only 80-odd seats for the party.

"This is a mandate for change," said the presumptive chief minister Sarbananda Sonowal, adding that illegal immigration from Bangladesh, sealing of the Indo-Bangla border and unemployment would be his government's biggest challenges.

Sonowal is expected to meet with senior party functionaries in Guwahati later today to discuss the government formation. Afterwards, he and Sarma will fly to New Delhi with a list of prospective ministers.

Putting together this list, though, will present the first major challenge to Sonowal and Sarma. They have to ensure ministerial representation to all regions and communities, not to mention various factions within the party. The BJP had a pre-poll alliance with the AGP and the BPF as well as local parties representing Rabha and Tiwa tribal communities, and they are all likely to demand a place in the cabinet.

The BJP would be pressed to have a Muslim minister given the huge support it got from the community

The BPF is said to be demanding at least four ministerial berths. The party was expected to win 6-8 seats of the 16 it contested. At last count, it had won 10 and was leading on two.

The AGP, which is set to win over a dozen seats, would have an even bigger claim. The party is nearly vertically split between the factions led by its chief Atul Bora, who has won from Bokakhat, and former chief minister Prafulla Kumar Mahanta, who has returned to the assembly from Barhampur. Though Bora has greater influence in the party now, the BJP leadership is unsure how long Mahanta would be content with an "inferior position".

According to sources in the AGP, Bora's camp had decided ahead of the election to keep Mahanta "at a safe distance due of his tarnished image". They brought such pressure to bear on him that Mahanta had declare he would confine himself to campaigning within his constituency.

But five days ago, Mahanta raised the BJP's heckles by saying that Sonowal would not be acceptable as chief minister since he wasn't a unanimous choice of all partners in the alliance. He had even invited his partymen to discuss the issue over dinner at his house but not many turned up. The tussle between the two AGP elders could intensify in the coming days as both would seek to install more of their supporters in the ministry.

As for ministerial aspirants within the BJP itself, a senior functionary said a few candidates who were certain of winning had started lobbying for berths in the cabinet even before the results were declared. He warned that the euphoria over the victory could give way to dissension if some of these legislators were not included in the ministry.

The BJP would be pressed to include at least one Muslim in the ministry given the significant support it received from the community at various places. For one, Narayan Deka, who unexpectedly wrested the Congress bastion of Barkhetri in Nalbari, could not have won without the support of thousands of Muslims. There are several similar examples from western Assam and Barak Valley.

Considering that the BJP has described employment and infiltration from Bangladesh as the biggest challenges for the new regime, it would have to appoint efficient people to handle finance and home affairs. That won't be easy as only a handful among the BJP legislators have any ministerial experience.